The Genie 77303GT is a genuine OEM Counterbalance Valve, 3500 PSI designed for Genie S series telescopic boom lifts and Z series articulating boom lifts. Sourced directly from Genie, this valve meets the original hydraulic circuit specifications for the models it serves, ensuring correct load-holding pressure and controlled cylinder movement. It fits an extensive range of S series and Z series booms — including models S-80X, S-80, S-85, S-60, S-65, S-60X. When you need a verified, direct replacement for a failed or leaking counterbalance valve, this genuine OEM component is the dependable answer.
Key Features
- Genuine OEM Hydraulic Precision — Manufactured to Genie's original pressure specifications, this valve holds the 3500 PSI rating required to properly regulate load-induced pressure in the boom's hydraulic cylinder circuits.
- Direct-Replacement Hydraulic Valve — Engineered to install into the existing hydraulic circuit without rework, matching port sizing, thread configuration, and ATM vent designation of the original valve.
- Broad S and Z Series Compatibility — Fits a wide range of Genie telescopic and articulating boom lifts, including S-40 through S-85 variants and Z-45 through Z-62 series, covering IC power, DC, Bi-Energy, XC, TRAX, HF, and FE Hybrid configurations.
- Load Control Integrity — A properly functioning counterbalance valve prevents uncontrolled boom drift or descent under load, maintaining smooth, stable platform movement during operation and positioning.
- Critical Safety Function — On aerial boom lifts, this valve is a primary safeguard against unintended boom movement if a hydraulic line fails or pressure is lost downstream — making correct valve specification essential for aerial work safety and compliance.
A counterbalance valve is a hydraulic control component installed in the cylinder circuit of a boom lift to hold a load securely in place and prevent uncontrolled movement. It works by requiring a minimum pilot pressure from the opposite side of the circuit before allowing the cylinder to retract or lower, meaning the boom cannot drift down on its own if hydraulic pressure drops unexpectedly. When a counterbalance valve fails — through internal leakage, seal deterioration, or improper cracking pressure — the result can be slow boom drift, jerky or uncontrolled lowering, or an inability to hold the platform at height, all of which present serious operational and safety concerns on an aerial lift.
Part Details
| Part Number | 77303GT |
|---|---|
| Brand | Genie |
| Part Type | Genuine OEM |
| Description | Counterbalance Valve, 3500 PSI, ATM Ven |
Compatibility & Fitment
| Name | Model |
|---|---|
| S-80X | S-80X |
| S-80 | S-80 |
| S-85 | S-85 |
| S-60 | S-60 |
| S-65 | S-65 |
| S-60X | S-60X |
| S-60 XC | S-60 XC |
| S-60 HC | S-60 HC |
| S-60 TRAX | S-60 TRAX |
| S-65 TRAX | S-65 TRAX |
| S-65 XC | S-65 XC |
| S-60 HF | S-60 HF |
| S-65 HF | S-65 HF |
| S-40 | S-40 |
| S-45 | S-45 |
| S-80 XC | S-80 XC |
| S-85 XC | S-85 XC |
| S-80 HF | S-80 HF |
| S-85 HF | S-85 HF |
| S-40 XC | S-40 XC |
| S-45 XC | S-45 XC |
| S-40 TRAX | S-40 TRAX |
| S-45 TRAX | S-45 TRAX |
| S-40 HF | S-40 HF |
| S-45 HF | S-45 HF |
| S-60 J | S-60 J |
| S-80 J | S-80 J |
| S-60 FE Hybrid | S-60 FE Hybrid |
| S-60 DC | S-60 DC |
| TZ-34/20 | TZ-34/20 |
| Z-51/30J | Z-51/30J |
| Z-45/25 | Z-45/25 |
| Z-45/25J IC Power | Z-45/25J IC Power |
| Z-45/25J DC | Z-45/25J DC |
| Z-45/25J Bi-Energy | Z-45/25J Bi-Energy |
| Z-40/23N | Z-40/23N |
| Z-40/23N RJ | Z-40/23N RJ |
| Z-62/40 | Z-62/40 |
| Z-45 XC | Z-45 XC |
| Z-60/37 DC | Z-60/37 DC |
| Z-60/37 FE Hybrid | Z-60/37 FE Hybrid |
| Z-45/25 IC | Z-45/25 IC |
| Z-60 DC | Z-60 DC |
| Z-60 FE Hybrid | Z-60 FE Hybrid |
| Z-60 FE | Z-60 FE |
| Z-45/25J IC | Z-45/25J IC |
| Z-45/22 | Z-45/22 |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
